Birsen Bilgici

Oxidative stress induced by 1.8 GHz radio frequency electromagnetic radiation and effects of garlic extract in rats.

Abstract Purpose: We aimed to study the oxidative damage induced by radiofrequency electromagnetic radiation (RF-EMR) emitted by mobile telephones and the protective effect of garlic extract used as an anti-oxidant against this damage. Materials and methods: A total of 66 albino Wistar rats were divided into three groups. The first group of rats was given 1.8 GHz, 0.4 W/kg specific absorption rate (SAR) for 1 h a day for three weeks. The second group was given 500 mg/kg garlic extract in addition to RF-EMR. The third group of rats was used as the control group. At the end of the study, blood and brain tissue samples were collected from the rats. Results: After the RF-EMR exposed, the advanced oxidation protein product (AOPP) levels of brain tissue increased compared with the control group (p < 0.001). Garlic administration accompanying the RF-EMR, on the other hand, significantly reduced AOPP levels in brain tissue (p < 0.001). The serum nitric oxide (NO) levels significantly increased both in the first and second group (p < 0.001). However, in the group for which garlic administration accompanied that of RF-EMR, there was no difference in serum NO levels compared with the RF-EMR exposed group (p > 0.05). There was no significant difference among the groups with respect to malondialdehyde (MDA) levels in brain tissue and blood samples (p > 0.05). Similarly, no difference was detected among the groups regarding serum paroxonase (PON) levels (p > 0.05). We did not detect any PON levels in the brain tissue. Conclusions: The exposure of RF-EMR similar to 1.8 GHz Global system for mobile communication (GSM) leads to protein oxidation in brain tissue and an increase in serum NO. We observed that garlic administration reduced protein oxidation in brain tissue and that it did not have any effects on serum NO levels.

Effect of 900 MHz radiofrequency radiation on oxidative stress in rat brain and serum.

The increasing use of mobile telephones raises the question of possible adverse effects of the electromagnetic fields (EMF) that these phones produce. In this study, we examined the oxidative stress in the brain tissue and serum of rats that resulted from exposure to a 900-MHz EMF at a whole body average specific absorption rate (SAR) of 1.08 W/kg for 1 h/day for 3 weeks. We also examined the antioxidant effect of garlic powder (500 mg/kg/day) given orally to EMF-exposed rats. We found that malondialdehyde (MDA) (p < 0.001) and advanced oxidation protein product (AOPP) (p < 0.05) increased in rat brain tissue exposed to the EMF and that garlic reduced these effects (p < 0.05). There was no significant difference in the nitric oxide (NO) levels in the brain. Paraoxonase (PON) was not detected in the brain. There was a significant increase in the levels of NO (p < 0.001) detected in the serum after EMF exposure, and garlic intake did not affect this increase in NO. Our results suggest that there is a significant increase in brain lipid and protein oxidation after electromagnetic radiation (EMR) exposure and that garlic has a protective effect against this oxidative stress.

Oxidative stress in bipolar and schizophrenia patients

Oxidative stress has an important place in studies investigating the pathophysiology of psychiatric diseases. In spite of this fact, longitudinal studies are required to clarify the subject. Therefore, in this study, we examined lipid peroxidation, protein oxidation, total oxidized guanine species, superoxide dismutase (SOD) and total glutathione (GSH) levels in blood collected from adult bipolar patients (n=18) during manic and euthymic episodes, schizophrenic patients (n=18) during acute psychotic attack and remission phases and the control group (n=18). There was a significant increase in the level of lipid peroxidation in the bipolar disorder manic episode group (BD-ME) compared to control group. The level of protein oxidation was significantly higher in the schizophrenia acute psychotic attack group (SZ-APA) compared to the control group. The level of total oxidized guanine species was statistically higher in all psychiatric groups compared to the control group. There was no significant difference among the groups with regard to SOD and GSH. Consequently, we believe that lipid peroxidation may be effective in the pathogenesis of bipolar patients; that protein oxidation may be of importance in the pathogenesis of schizophrenia and that total oxidized guanine species may be crucial in the pathogeneses of both psychiatric disorders.

Changes in IGF-I, IGFBP-3 and ghrelin levels after adenotonsillectomy in children with sleep disordered breathing

OBJECTIVE The aim of this study was to determine the changes in insulin-like growth factor-I (IGF-I), insulin-like growth factor binding protein-3 (IGFBP-3) and ghrelin levels following adenotonsillectomy (T&A) in children with sleep disordered breathing (SDB). METHODS Forty children (mean age 4.85+/-2.15 years) clinically diagnosed with adenotonsillar hypertrophy (ATH) related SDB were enrolled. All children underwent T&A. Serum levels of IGF-I, IGFBP-3 and ghrelin were measured before and 6 months after T&A. RESULTS Serum levels of IGF-I and IGFBP-3 were significantly higher after T&A (p<0.001). Serum ghrelin levels showed a significant decrease after T&A (p<0.001). CONCLUSION Children with ATH related SDB who underwent T&A showed significant increases in IGF-I and IGFBP-3 levels indicating an increase in diurnal growth hormone secretion as well as a significant decrese in ghrelin levels indicating an increased oral food intake in the postoperative period.

Assessment of Genotoxicity in Rats Treated With the Antidiabetic Agent, Pioglitazone

Pioglitazone (PIO), a member of the thiazolidinedione class of antidiabetic agents, specifically targets insulin resistance. Drugs of this class act as ligands for the gamma subtype of the peroxisome proliferator‐activated receptor. Although troglitazone, another drug in this class, displayed unacceptable hepatotoxicity, PIO was approved for human use by the U.S. Food and Drug Administration. To our knowledge, there are no published reports on the genotoxicity of PIO; however, the package insert indicates that it has minimal genotoxicity. In this study, we used the comet assay to investigate the DNA damage in the peripheral blood and liver cells of rats treated with PIO. Sixteen male Sprague‐Dawley rats were randomly distributed into four groups, and dosed daily for 14 days by oral gavage with 0, 10, 20, and 40 mg/kg/day PIO. A dose‐dependent increase in DNA damage, as assessed by % tail DNA, was observed in both hepatocytes and blood lymphocytes of the PIO‐treated groups, with significant increases detected between the rats treated with all the doses of PIO and the control, and between the rats treated with different PIO doses (P < 0.005 to P < 0.0001). Treating nuclei from the exposed animals with an enzyme cocktail containing Fpg and Endonuclease III prior to performing the comet assay increased the level of DNA damage, which reflects oxidized purine and pyrimidine. Taken together, our data indicate that PIO is able to dose‐dependently induce DNA damage in both the liver and blood lymphocytes of rats, which is partially due to the generation of oxidative lesions. Environ. Mol. Mutagen., 2008.

Evaluation of body weight, insulin resistance, leptin and adiponectin levels in premenopausal women with hyperprolactinemia

The effects of hyperprolactinemia on metabolic parameters are not clear and a few data evaluating adiponectin levels in prolactinoma and idiopathic hyperprolactinemia exist. The aim of this study was to evaluate the effects of hyperprolactinemia on body weight, insulin resistance, beta cell function, and leptin and adiponectin levels in premenopausal women with hyperprolactinemia. Forty premenopausal women with prolactinoma or idiopathic hyperprolactinemia were compared to 41 age-matched healthy premenopausal women with regard to body weight, body mass index, waist and hip circumferences, waist to hip ratio, fasting plasma glucose, insulin levels, insulin resistance measured by homeostasis model assessment (HOMA)-insulin resistance index, beta cell function measured by HOMA-β index, leptin and adiponectin levels. Plasma insulin levels and HOMA indexes (both insulin resistance and beta indexes) were significantly higher in hyperprolactinemic women. The other parameters were similar between both groups. There was a positive correlation between prolactin levels and fasting plasma glucose in hyperprolactinemic women. The results of this study showed that high prolactin levels may be associated with hyperinsulinemia and insulin resistance in premenopausal women. This effect seems to be independent of body weight, leptin and adiponectin levels. High prolactin levels may directly stimulate insulin secretion from pancreas and directly cause hepatic and whole-body insulin resistance.

Influence of α-tocopherol and α-lipoic acid on bisphenol-A-induced oxidative damage in liver and ovarian tissue of rats.

Bisphenol A (BPA) is a commonly used material in daily life, and it is argued to cause oxidative stress in liver and ovarian tissue. α-Lipoic acid (ALA) and α-tocopherol (ATF), two of the most effective antioxidants, may play a role in preventing the toxic effect. Therefore, the purpose of this study was to examine the beneficial effects of ALA, ATF, and that of ALA + ATF combination on oxidative damage induced by BPA. Female Wistar rats were divided into five groups (control, BPA, BPA + ALA, BPA + ATF, and BPA + ALA + ATF). BPA (25 mg/kg/day), ALA (100 mg/kg/day), and ATF (20 mg/kg/day) were administered for 30 days.  The levels of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT), liver malondialdehyde (L-MDA) and glutathione peroxidase (L-GPx), and ovarian malondialdehyde (Ov-MDA) and nitric oxide (Ov-NO) were significantly higher in the BPA-treated groups compared with the control group. The levels of AST and ALT decreased in the BPA + ALA, BPA + ATF, and BPA + ALA + ATF groups compared with the BPA group. Similarly, BPA + ALA or BPA + ATF led to decreases in L-MDA and Ov-MDA levels compared with the BPA group. However, the BPA + ALA + ATF group showed a significant decrease in L-MDA levels compared with the BPA + ALA group and the BPA + ATF group. The levels of L-GPx decreased in the BPA + ATF and the BPA + ALA + ATF groups compared with the BPA group. The administration of ATF and ALA + ATF significantly decreased the Ov-NO levels.  This study demonstrates that BPA causes oxidative damage in liver and ovarian tissues. ALA, ATF, or their combination were found to be beneficial in preventing BPA-induced oxidative stress.

Adipocytokines and ghrelin level of bipolar patients from manic episode to euthymic episode

Abstract Purpose: Obesity and metabolic syndrome (MeS) are more frequently observed in bipolar patients than the general population. This may result from the differences of adipocytokines and ghrelin levels in bipolar disorder. Material and methods: We evaluated the leptin, adiponectin, resistin and ghrelin levels in bipolar patients (n = 30) in manic episode and in a control group (n = 30). After treatment, the same patients were evaluated again during the euthymic episode. We also measured the insulin, glucose, insulin resistance (HOMA), trygliceride (TG), total cholesterol (TCHOL), high density lipoprotein cholesterol (HDL) and low density lipoprotein cholesterol (LDL) in relation to the (MeS). Results: When controlling for age, BMI and glucose, leptin levels were higher in the bipolar disorder manic episode group (BD-ME) and bipolar euthymic episode group (BD-EE) than the control group; resistin levels were higher in the BD-ME compared to the control group and it had a positive correlation with Young Mania Rating Scale (YMRS). After treatment, ghrelin levels were higher in the BD-EE compared to the BD-ME group. There was no difference among the groups with respect to adiponectin. Conclusions: The present results point that high leptin, resistin and ghrelin levels may be involved in the early pathophysiological process which can lead to later obesity and MeS in patients with bipolar disorder.

Effect of bisphosphonate as an adjunct treatment for chronic periodontitis on gingival crevicuar fluid levels of nuclear factor-κB ligand (RANKL) and osteoprotegerin in postmenopausal osteoporosis

Osteoporosis and periodontal disease are linked by an altered receptor activator of nuclear factor κB ligand and osteoprotegerin ratio (RANKL/OPG), and medical treatment with bisphosphonate (BP) may help control these molecules. The effect of BP on clinical findings and gingival crevicular fluid (GCF) values of RANKL and OPG using enzyme-linked immunosorbent assays was evaluated in postmenopausal women; 13 patients with both chronic periodontitis and osteoporosis (group A), 12 systemically healthy patients with chronic periodontitis (group B), 12 periodontally healthy patients with osteoporosis (group C), and 10 systemically and periodontally healthy individuals (group D). Recordings were repeated at the end of months 1, 6, and 12 in groups A, B, and C. At the baseline, groups A and B exhibited the lowest OPG values (P < 0.05). After periodontal treatment, OPG values were markedly increased at the end of 6th month in group A and 12th month in group B (P < 0.008). There was no significant difference in GCF RANKL values among groups (P > 0.05) or during the observation period (P > 0.008). The use of BP may be effective in preventing periodontal breakdown by controlling the levels of these markers in osteoporosis as an adjunct to periodontal treatment.

An evaluation of vitamin D levels in children with seasonal allergic rhinitis during pollen season

Serum vitamin D levels have not been studied in children with seasonal allergic rhinitis (SAR). The aim of this study was to evaluate the vitamin D levels of children with SAR and to compare them to levels in healthy children during pollen season.